Quote Originally Posted by ConcinnusMan View Post
Awesome! I would love to see it myself. From a very early age, moving from WA to San Diego and back, and living in various locations in CA, I too noticed the wide variation of color in those frogs. I was completely shocked when I first got to San Diego and found the frogs living in canyon bottom. All the frogs there were metallic gold, metallic silver, or metallic bronze. I mean, they looked like metal. There were also a few like you mentioned that looked mottled with varying shades of brown but if I placed them in greenery for a while, large portions of their bodies would turn military green. The environment they lived in was dead and brown much of the year, but in late winter-early spring during the rainy season, the area would turn very green leaving any brown frogs at a disadvantage. The ability to change from brown to green and back must have been very necessary in a place like that. The metallic one's were usually not found out and about in vegetation. I'd always find those hunkered down in muddy banks. There was a lot of varying colored clay in the soil so they blended right in.
There was a study done on the ability of Pseudacris regilla's color-changing abilities, where they stuck the frogs in white-wall enclosures as well as ones with different shades/hues of greens and browns. Then they shone varying wavelengths of light upon them and monitored the frogs' color changes over time. The study noted complete changes from green to brown and back at specific wavelengths, some transitions taking days, even weeks. Not all frogs however changed color. I personally have noticed the changed in less than a day in my outside tanks, where they feel at home and get real sun.

I am sorry I don't have the study at hand, or even what it was called, but the study additionally confirmed that while most all of these frogs have the ability to lighten and darken (just like a basking blue-belly fencie going dark,) only a portion of the gene pool displays phenotypically observable total color changing abilities (green to brown, etc.) The rest are typically either green or brown; grays, olives, and tans exist as well but are less common. It has been noted that while the browns and greens can lighten and darken, they will always be either brown or green. The color-changers, while being able to swap greens and browns, usually can't achieve the bold examples of either colors found in the non-changers. Add to this that these guys can be bi-colored (brown and green - usually with a pattern), then add the metallic sheens of copper, silver, bronze, and gold (a phenomenon I have witnessed with juvenile frogs as well as with basking adults - I think basking may play a role with metallics, as they come and go like the weather) well, it all just beckons more research!

What has been discovered is that populations of Pseudacris throughout California commonly have this 3-way ability to be either green, brown, or changeable, and that this strategy helps any such population to endure fluctuating seasonal weather patterns. Easy to see how browns might be better camouflaged in a dry year and so forth...

That means there's a unique mix of genes in these pools that all the variants probably carry. One of my questions is: Is it random genetics at play here, or does there exist a biological mechanism to detect changing weather conditions which can turn some switches on and off, so as to prepare for a more appropriate color. Might be a long-term study with multiple sites. Perhaps during a wet year there was a hypothetical population crash because not enough greens were produced. That might then negate any color preparation, proving randomness. I just don't think it's all so random. Nature's always more infinitely complex than our own assumptions and usually our own discoveries as well.

And now it's not just P. regilla anymore. Pacific Chorus Frogs have been newly divided into 3 separate species: P. regilla (Northern Pacific,) P. sierra (Sierran,) and P. hypochondriaca (Baja CA.)

How does all this relate to garter snakes? (since this is all about frogs...) Well, I can't say I know exactly how a garter sees, but I do know, being primarily diurnal, they probably can see a lot better than many other snakes. ...And as we all know, snakes have excellent blind sight. Their motion detection is incredible!

It all about not being seen! On that note, I recommend everyone look up Monty Python's "How not to be seen" on YouTube.

Steve